SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47ef22c1c4121924da6b78a104aecda203df9361b865ff75035dc386c9eb0f28' 
  AND token = 'ULbPEZQKFIR3w27Op6r8Ow2EPZKAeqXnam+rvQT9pGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}